Current cytometer cartridges have several limitations. Current cytometer cartridges require two orders of magnitude more sheath fluid than sample fluid. This volume of sheath fluid makes up most of the waste fluid and requires a relatively large cartridge size. Current cytometer cartridges require an optical system that resides on the cytometer instrument and that precisely aligns with the cytometer instrument and the illumination source and detectors of the instrument. Current cartridges further need to be able to search for, and lock onto, the stream of cells within the measurement channel. Current cartridges limit the range of scatter angles that can be detected to those angles that are much smaller than 30 degrees. Current cartridges require a precise sample via to inject sample into the reagent channel. Additionally, the dimensional tolerance of the sample via is one of the smallest on the cytometer cartridge card.